On Tue, Feb 15, 2022 at 04:42:46PM +0100, Fabrice Gasnier wrote:
> On 2/15/22 3:04 PM, Greg KH wrote:
> > On Tue, Feb 15, 2022 at 12:04:19PM +0100, Fabrice Gasnier wrote:
> >> When the gadget driver hasn't been (yet) configured, and the cable is
> >> connected to a HOST, the SFTDISCON gets cleared unconditionally, so the
> >> HOST tries to enumerate it.
> >> At the host side, this can result in a stuck USB port or worse. When
> >> getting lucky, some dmesg can be observed at the host side:
> >> new high-speed USB device number ...
> >> device descriptor read/64, error -110
> >>
> >> Fix it in drd, by checking the enabled flag before calling
> >> dwc2_hsotg_core_connect(). It will be called later, once configured,
> >> by the normal flow:
> >> - udc_bind_to_driver
> >> - usb_gadget_connect
> >> - dwc2_hsotg_pullup
> >> - dwc2_hsotg_core_connect
> >>
> >> Fixes: 17f934024e84 ("usb: dwc2: override PHY input signals with usb role switch support")
> >> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
> >> ---
> >> Changes in v2:
> >> - Fix build error: 'struct dwc2_hsotg' has no member named 'enabled';
> >> as reported by the kernel test robot.
> >> https://lore.kernel.org/all/202202112236.AwoOTtHO-lkp@xxxxxxxxx/
> >> Add dwc2_is_device_enabled() macro to handle this.
> >> ---
> >> drivers/usb/dwc2/core.h | 2 ++
> >> drivers/usb/dwc2/drd.c | 6 ++++--
> >> 2 files changed, 6 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> >> index 8a63da3..8a7751b 100644
> >> --- a/drivers/usb/dwc2/core.h
> >> +++ b/drivers/usb/dwc2/core.h
> >> @@ -1418,6 +1418,7 @@ void dwc2_hsotg_core_connect(struct dwc2_hsotg *hsotg);
> >> void dwc2_hsotg_disconnect(struct dwc2_hsotg *dwc2);
> >> int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode);
> >> #define dwc2_is_device_connected(hsotg) (hsotg->connected)
> >> +#define dwc2_is_device_enabled(hsotg) ((hsotg)->enabled)
> >
> > Why the extra ()? dwc2_is_device_connected does not have it, so this
> > one probably should not either, right?
>
> Hi Greg,
>
> I was wondering the same, checkpatch complains without it:
>
> CHECK: Macro argument 'hsotg' may be better as '(hsotg)' to avoid
> precedence issues
checkpatch is wrong here, this is a structure pointer, not anything you
could ever use that could be evaluated any other way.
> I can remove the extra () in a v3 if you wish ?
Please do.
thanks,
greg k-h
